CVE-2026-47959: 
Adobe Acrobat Classic vulnerability analysis and mitigation

CVE-2026-47959 is a Stack-based Buffer Overflow vulnerability (CWE-121) in Adobe Acrobat and Acrobat Reader that could allow arbitrary code execution in the context of the current user. It affects Adobe Acrobat and Acrobat Reader versions 26.001.21651 and earlier, as well as Acrobat 2024 versions 24.001.30365 and earlier, on both Windows and macOS platforms. Adobe disclosed and patched this vulnerability on June 9, 2026. It carries a CVSS v3.1 base score of 7.8 (High) (Adobe Advisory).

The vulnerability is classified as CWE-121 (Stack-based Buffer Overflow), where insufficient bounds checking during file parsing allows a specially crafted PDF or document to overflow a stack buffer. An attacker exploits this by crafting a malicious file that, when opened by a victim in Acrobat Reader, triggers the overflow and redirects execution flow to attacker-controlled code. The attack vector is local (the file must be delivered and opened by the user), requires no privileges, but does require user interaction — the victim must open the malicious file. No public proof-of-concept or technical write-up has been identified at this time (Adobe Advisory).

Successful exploitation allows an unauthenticated attacker to execute arbitrary code in the security context of the current user, potentially leading to full compromise of the user's session, data exfiltration, installation of malware, or further lateral movement within the network. All three security dimensions are affected at high severity: confidentiality, integrity, and availability. The scope is limited to the affected system and user context, but in enterprise environments where Acrobat is widely deployed, the risk of phishing-based delivery of malicious PDFs is significant (Adobe Advisory).

1. Craft malicious file: An attacker creates a specially crafted PDF or supported document file designed to trigger the stack-based buffer overflow in Adobe Acrobat Reader's file parsing routines.
2. Deliver the file: The attacker delivers the malicious file to the target via phishing email, malicious download link, or other social engineering methods.
3. Victim opens the file: The victim opens the malicious file using a vulnerable version of Adobe Acrobat or Acrobat Reader (≤26.001.21651 or ≤24.001.30365).
4. Trigger buffer overflow: The malformed file content causes a stack buffer to be overwritten, corrupting the return address or function pointer on the stack.
5. Achieve code execution: The overwritten control data redirects execution to attacker-controlled shellcode or a ROP chain, resulting in arbitrary code execution as the current user (Adobe Advisory).

• File System: Presence of unexpected or suspicious PDF files in user download directories, temp folders, or email attachment staging areas; new executables or scripts created in user-writable directories shortly after a PDF was opened.
• Process: Unusual child processes spawned by AcroRd32.exe or Acrobat.exe (e.g., cmd.exe, powershell.exe, curl, wscript.exe); Acrobat processes making unexpected outbound network connections.
• Network: Outbound connections from Acrobat processes to unknown or suspicious IP addresses or domains, particularly shortly after opening a PDF file.
• Logs: Windows Event Logs showing application crashes or access violations in Acrobat Reader processes; security tool alerts on stack pivot or shellcode execution patterns associated with Acrobat.

Adobe released patched versions on June 9, 2026: users should update Adobe Acrobat and Acrobat Reader to version 26.001.21662 or later, and Acrobat 2024 to version 24.001.30383 or later. As a workaround, organizations should educate users to avoid opening PDF files from untrusted or unexpected sources, and consider implementing sandboxing or file inspection solutions for PDF processing in high-risk environments. Enabling Adobe's Protected Mode and Protected View settings can also reduce the attack surface by restricting what malicious documents can execute (Adobe Advisory).

The vulnerability was included in Adobe's June 2026 security patch release, which covered multiple products. Security aggregators including Tenable (Nessus plugin 320125), INCIBE-CERT, and CISA's weekly vulnerability bulletin (SB26-166) referenced the issue. No notable independent researcher commentary or significant social media discussion has been identified beyond standard patch-cycle coverage.